Unverified Commit 303c6619 authored by Tommaso Tocci's avatar Tommaso Tocci
Browse files

intercept dup, dup2, dup3

parent c294d9e0

include/client/hooks.hpp

+3 −0
Original line number Diff line number Diff line
@@ -27,6 +27,9 @@ int hook_write(int fd, void* buf, size_t count); 
int hook_unlink(const char* path);

int hook_access(const char* path, int mask);

int hook_lseek(unsigned int fd, off_t offset, unsigned int whence);

int hook_dup(unsigned int fd);

int hook_dup2(unsigned int oldfd, unsigned int newfd);

int hook_dup3(unsigned int oldfd, unsigned int newfd, int flags);





#endif

src/client/hooks.cpp

+25 −0
Original line number Diff line number Diff line
@@ -156,3 +156,28 @@ int hook_lseek(unsigned int fd, off_t offset, unsigned int whence) { 
   return syscall_no_intercept(SYS_lseek, fd, offset, whence);

}



int hook_dup(unsigned int fd) {

    CTX->log()->trace("{}() called with oldfd {}", __func__, fd);

    if (CTX->file_map()->exist(fd)) {

        return with_errno(adafs_dup(fd));

    }

    return syscall_no_intercept(SYS_dup, fd);

}



int hook_dup2(unsigned int oldfd, unsigned int newfd) {

    CTX->log()->trace("{}() called with fd {} newfd {}", __func__, oldfd, newfd);

    if (CTX->file_map()->exist(oldfd)) {

        return with_errno(adafs_dup2(oldfd, newfd));

    }

    return syscall_no_intercept(SYS_dup2, oldfd, newfd);

}



int hook_dup3(unsigned int oldfd, unsigned int newfd, int flags) {

    if (CTX->file_map()->exist(oldfd)) {

        // TODO implement O_CLOEXEC flag first which is used with fcntl(2)

        // It is in glibc since kernel 2.9. So maybe not that important :)

        CTX->log()->warn("{}() Not supported", __func__);

        return -ENOTSUP;

    }

    return syscall_no_intercept(SYS_dup3, oldfd, newfd, flags);

}

src/client/intercept.cpp

+16 −0
Original line number Diff line number Diff line
@@ -96,6 +96,22 @@ static inline int hook(long syscall_number, 
                             static_cast<unsigned int>(arg2));

        break;



    case SYS_dup:

        *result = hook_dup(static_cast<unsigned int>(arg0));

        break;



    case SYS_dup2:

        *result = hook_dup2(static_cast<unsigned int>(arg0),

                            static_cast<unsigned int>(arg1));

        break;



    case SYS_dup3:

        *result = hook_dup3(static_cast<unsigned int>(arg0),

                            static_cast<unsigned int>(arg1),

                            static_cast<int>(arg2));

        break;



    default:

        /*

         * Ignore any other syscalls

         * i.e.: pass them on to the kernel